Abstract
In the production of Mule-ducks, the author have obtained the following resultsin the fertility tests using the undiluted and diluted semen secured from the Muscovy male by means of the side-collection method.
1. Undiluted semen is superior to various diluted semen in absolute and relative fertility.
2. Fertility potential of the undiluted semen is maintained for 8 days in average, i. e., longer than in the case of the variously (from 3 to 10 times) diluted semen.
3. Eight times as much volume of semen is secured from the Muscovy by means of the side-collection method as by the previously reported electro-ejaculation method. The sperm concentration does not differ greatly between the semen obtained bythe two methods.
4. Judging from the sperm concentration, the volume of the undiluted semen which can be secured from one male at one time is sufficient to provide semen for 89 female birds. Therefore, it does not seem that the injection of undiluted semen reduce the meaning of artificial insemination.
